NASA FACTS is a collection of the United States' National Aeronautics and Space Administration's science series, NASA FACTS, intended as "easy-to-understand explanations of scientific phenomena involved in projects undertaken by NASA". The NASA FACTS SCIENCE SERIES was published frequently at irregular intervals, each presenting "an analysis of a particular subject within program perimeters and scientific disciplines of interest to NASA".

(quote from this cover letter from Director, Educational Programs Division of NASA's Office of Public Affairs, James V. Bernardo.)

"Whatever space exploration or investigation is planned, the instruments package or the astronauts, or both, must first be put into space. This is the job of the launch vehicle.

A launch vehicle is any device that propels and guides a spacecraft into space, whether for a probe (from which it falls back directly to earth), into orbit about the earth, or into a trajectory to another celestial body.

The launch vehicle must apply a thrust large enough, and long enough, to lift the entire rocket, which also includes the control system and the payload. As the fuel burns in the chamber, the gases expand through a nozzle at high velocity, creating reaction in the opposite direction.

"Advanced equipment designed and proposed for use in future weather satellite systems is being tested in NASA's Project Nimbus. The first Nimbus satellite, designated Nimbus I, was launched August 28, 1964. Nimbus is a second generation meteorological satellite program., It was preceded by the successful TIROS project which, by making possible increased observations of the earth's atmosphere, contributes to accuracy of weather forecasts and to the extension of meteorological knowledge.

Nimbus I provided the first pictures of the earth's surface and of cloud patterns ever taken by a weather satellite at night. TIROS satellites are limited in their observations to the earth's sunlit side. The Nimbus I achievement points the way to around-the-clock weather coverage by satellite.

The excellent quality pictures taken by Nimbus at night were achieved by means of its High- Resolution Infrared Radiometer (HRIR) system. The system detects minute differences in the relatively faint invisible infrared radiation (heat) emitted by clouds and the earth's surface. It converts the data to electrical signals that are stored on magnetic tape for transmission on command to earth.

When the signals are received an earth, they are fed to facsimile recorders that turn them into a strip of pictures. The shades (lightness or darkness) of images in the pictures are directly related to the infrared radiation emitted by the pictured objects, for example, water areas such as seas, oceans, lakes, and rivers) appear dark because ..." view page 1, page 2, page 3, page 4, page 5, page 6, page 7, page 8

"Before man can journey safely to the moon, he must acquire information that has defied centuries of observation. An important step toward meeting this requirement is NASA's Project Ranger which, on July 31, 1964, gave man a closer look than ever before at the moon.

Knowledge of the moon has been based largely on observations through telescopes on earth. This knowledge is seriously limited by the moon's great distance from earth and by earth's atmosphere, which veils or distorts lunar images. The resolution, or ability to distinguish objects, of earth's most powerful telescopes permits man to detect lunar objects no smaller than a half mile in size.

Ranger VII, launched July 28, 1964, telecast pictures to earth that revealed lunar features as small as 15 inches across. The craft transmitted the photographs on July 31 before it crashed in the northwest corner of Mare Nubium -- the Sea of Clouds -- about eight miles from its targeted impact area. This area now has been designated the Mare Cognitum by the International Astronomical Union. The term Mare, which is seain latin, was given to certain areas of the moon by..."read full report----

Image:NASA FACTS PROJECT RELAY G-12-62 page 01.jpg "Within five years, advances in space technology may create an operational communications satellite system that will vastly increase intercontinental telephone, telegraph, and data exchange channels and make possible transocean television. Contributing to progress toward this new communications era is NASA's Relay satellite program.

Relay is designed to test intercontinental transmission of telephone, television, teleprint, and facsimile signals via a medium-altitude active-repeater satellite. It is also equipped to report on the functioning of its equipment and on radiation in space.

Medium-altitude is an arbitrary designation for altitudes from several thousand to about 12,000 miles. Active repeater signifies that Relay is equipped to receive, amplify, and transmit radio signals. Active-repeater satellites differ from passive communications satellites, such as Echo, in that the latter function simply as mirrors for reflection of radio signals. Relay is but one of several experimental communications satellite projects embarked upon by the United States. The different technical approaches of these programs are providing an extensive variety of information that is advancing the time when establishment of an operational system will be achieved.

"The first Relay satellite, launched December 13, 1962, could not at first function properly because of an abnormal power drain on its storage batteries. The problems relative to the satellite had been partially resolved by January 3, 1963, making possible the beginning of experiments in transatlantic communication.

On Relay's fifth orbit, some 14 hours after launch, the ground test station at Nutley, New Jersey, checked the satellite's condition. The satellite's voltage was indicated at 22.5, which is below the lower limit of 24 volts required for operation of the communications equipment with- damage to the battery.

The trouble was traced to the voltage regulator in the No. 1 transponder -- the receiving, amplifying, and transmitting apparatus in Relay.

Relay is equipped with two identical transponders, each with its own voltage regulator. The voltage regulator channels power to the transponder at a proper voltage and acts as an on-off switch for the transponder.

Telemetry showed that the regulator was conducting power to the transponder even though it was nominally off. As a result, it was partially powering the transponder, and draining the batteries.

TIROS, or Television Infrared Observation Satellite, NASA's forerunner to NIMBUS. According to Lyndon Johnson, TIROS was, based on its allowing meteorologists to accurately predict weather five days in advance, responsible for saving the United States over 6.5 billion dollars -- even though TIROS was able to send only 64 pictures per orbit.

"Carla... Donna... Esther... Flora... These were destructive hurricanes which took thousands of lives and caused millions of dollars in damage. Future counterparts, with other feminine names, will surely be as severe, but their destructive results will be minimized because people will be forewarned through information gathered by meteorological satellites in space, taking pictures of the earth's surface and cloud cover. Such warnings have enabled people in the hurricane belt to prepare themselves for high winds and water, and thus to spare lives and property. Such was the case with Carla.

The NASA weather satellite program which can detect hurricanes in their formative stages, and provide a great deal of other information useful to meteorologists is carried aut with TIROS. This satellite name is an acronym for Television Infrared Observation Satellite.

The International Space Station, which will be assembled between mid-1998 and 2003, will contain many Russian hardware elements developed in the nearly 30 years of the Russian space station program. The history of Russian space stations is one of gradual development marked by upgrades of existing equipment, reapplication to new goals of hardware designed for other purposes, rapid recovery from failures, and constant experimentation. The earliest Salyut stations were single modules, designed for only temporary operations. Mir, the most recent station, is a permanent facility in orbit since 1986 with a base made up of four separately-launched modules. Additional modules have been added to now total six laboratory modules and one docking module, added to allow the Space Shuttle to more easily dock with the station. U.S. Space Shuttles have been periodically docking with the Mir since July 1995. U.S. astronauts have maintained a permanent presence onboard Mir since March 1996 and that presence is expected to continue through 1998...read full report